The Nuts and Bolts of Antibiograms in Long-Term Care Facilities J. - PowerPoint PPT Presentation

The Nuts and Bolts of Antibiograms in Long-Term Care Facilities J. Kristie Johnson, Ph.D., D(ABMM) Professor, Department of Pathology University of Maryland School of Medicine Director, Microbiology Laboratories University of Maryland Medical Center jkjohnson@som.umaryland.edu March 6, 2018

Disclosures • Applied BioCode -Research Grant • Beckman Coulter-Speaker • bioMérieux-Speaker • M39 Working group member

Objectives • Review core concepts of antibiotic susceptibility and cumulative antibiotic susceptibility data/antibiograms • Identify best practices for developing and maintaining annual antibiograms in long-term care • Define how cumulative susceptibility data/antibiograms can be used in surveillance programs.

Antimicrobial Susceptibility Test • Only performed on bacteria in which susceptibility to standardized treatment is not predictable. – Predictable • β -Streptococcus – Not-predictable • E. coli • Antibiotics reported – Cascading antibiotics – Additional antibiotics fro MDROs – What methods – Breakpoints used

Antibiotic Susceptibility Testing Dilution and Disk Diffusion Dilution Diffusion Kirby Tube Agar E test Bauer Dilution Dilution Qualitative Quantitative

Terminology • Sensitive • Based on the pharmaco-dynamics of an antimicrobial agent administered according to the normally recommended dosage and the organism causing an infection, the agent will most likely inhibit the organism in vivo . • Intermediate (indeterminate)/Susceptible Dose Dependent …..might inhibit the organism in vivo. /Use higher dose • • • Resistant • …..will most likely not inhibit the organism in vivo. • Non-Susceptible • …..Not enough data to know if it is likely to inhibit the organism in vivo. • Epidemiological Cutoff Values • Determines the MIC of Wildtype and non-WT.

Where does the data come from? • Microbiology AST instruments • Microbiology LIS • Electronic Health Records (EHR) • Clinical decision support system (CDSS)

3 Types of Cumulative AST Data Reports 1. Traditional Antibiogram Local Level – A single facility 2. Enhanced Antibiogram 3. Non-Traditional Antibiograms – Combined Antibiograms Regional, National – Antimicrobial Resistance Surveillance Programs or Global

What Is An Antibiogram? • Presentation of cumulative antimicrobial susceptibility testing (AST) data from a single institution on an annual basis “Routine” Cumulative antibiogram Generally…all isolates from a facility CLSI, M39-A4

The Why? - Purpose of the Antibiogram • To help clinicians choose initial empiric therapy • Many more applications – Dr. Kim Claeys presentation on February 6 th discussed using the antibiogram for Antimicrobial Stewardship applications

Importance & Reliance on Antibiograms Grow! Courtesy of Trish Simner Direct from specimen diagnostics Direct from + blood diagnostics MALDI-TOF MS Traditional Methods: Same day ID & AST Day 2 Day 3 Day 0 Day 1 Standard AST panel Isolation of your organism Additional AST Collection and plating results available on solid media results of specimen in the lab • • Setup of additional MALDI-TOF MS ID • antimicrobials Set up of AST panels Empiric Treatment Narrowed Treatment Targeted Treatment 11

Who is Responsible for Creating the Antibiogram? • Traditionally the microbiology laboratory – Driven by access to the data from AST instruments or the LIS • Shifting towards stronger collaborations with Antimicrobial Stewardship Programs – Automated EHR based antibiograms • Should be a collaborative effort – Clinical microbiologists, pharmacists, physicians, IT specialists LIS: Laboratory Information System; EHR: Electronic Health Record; IT: Information Technology

Where Do You Start? • M39-A4: Analysis and Presentation of Cumulative Antimicrobial Susceptibility Test Data; Approved Guideline-Fourth Edition • M39-A5 currently being worked on. 2019-2020 – A newly created section on LTC

Preparation of Cumulative Antibiogram Recommendations • WHEN?-Analyze/present data at least annually • Include only verified final results • Include only species with ≥ 30 isolates • Include diagnostic (not surveillance) isolates • Include the 1 st isolate/patient ; no duplicate isolates • Only include routinely tested antimicrobial agents • Report only %S and do not include I% CLSI M39-A4

The Cumulative Antibiogram Report • Analyzes data from routine antimicrobial susceptibility tests performed in the clinical laboratory • Separate report prepared for each healthcare facility • Primarily used to guide empiric therapy • Sometimes used to monitor resistance – Changes in %S from year to year • Highly impacted by – patient population served – culturing practices • If cultures only performed when patients fail therapy – Laboratory antimicrobial susceptibility testing and reporting policies – Temporal outbreaks 15

Organism Specific Recommendations Bug/Drug Presentation of Data Streptococcus pneumoniae and List the %S using oral, meningitis and non-meningitis penicillin breakpoints Streptococcus pneumoniae and List the %S using meningitis and nonmeningitis cefotaxime, ceftriaxone, cefepime breakpoints Viridans group streptococci and List both the %S and %I penicillin Staphylococcus aureus List %S for all isolates and the methicillin-resistant S. aureus (MRSA) subset E. coli, K. pneumoniae and P. List % S using urine and non-urine breakpoints mirabilis and cefazolin CLSI M39-A4

Stratification of Antibiograms • Nursing site or site of care – ICU, burn unit, ED, outpatient clinic • Specimen type of infection site – Urine, blood • Clinical service or patient population – Surgical, pediatric, transplant, cancer

Answers to Commonly Asked Questions

How do I Apply Intrinsic Resistance? The most up-to-date Intrinsic Resistance tables are located in the current M100 document. CLSI, M100-S28.

What Do You Do With Susceptible Dose Dependent (SDD) Results? • SDD: an interpretive category defined by a breakpoint that susceptibility of an isolate is dependent on the dosing regimen that is used in the patient – Cefepime and Enterobacteriaceae – Fluconazole and C. albicans, C. glabrata, C. parapsilosis , & C. tropicalis – New in 2019: • Daptomycin and Enterococcus spp • Ceftaroline and Staphylococcus aureus – Report both % S & %SDD either in the Table or as a footnote N % S Cefepime %SDD Cefepime 92 a Escherichia coli 574 3 84 b Klebsiella pneumoniae 132 2 a : “In addition, to the 92% S results, 3% were SDD (MIC 4 to 8 µg/mL) and 5% were R (MIC >16 µg/mL) to cefepime”

Why Do We Need a Minimum of N=30? • Less statistical validity of data – Small numbers can skew the data How Reliable is a Report of 80% Susceptible for E. coli and Ciprofloxacin? Sample size % S (95% CI) 10 44 to 97 100 71 to 87 1000 77 to 82

What Do I Do If We Don’t Reach N≥30? • So what can you do? – Analyze multiple years – add footnote – Report the results from N < 30 with a footnote • “Calculated from fewer than the standard recommendation of 30 isolates” – Group several species within a genus together – Aggregate data from multiple smaller facilities with a similar patient population in the same geographic area Discuss more LTCF specific later

Enhanced Antibiogram

What Are Enhanced Antibiograms? • Segregating cumulative antibiogram data by one or more of the following: – Location – e.g., Inpatient vs Outpatient or ICU vs Oncology vs Non-ICU/Non- Oncology Wards – Specimen type – e.g. urine or blood specific – Clinical condition – e.g. cystic fibrosis, burn patients – Patient Age – e.g., pediatrics vs adults – Resistance Phenotype – e.g., MRSA, MSSA, carbapenem-resistant Enterobacteriaceae – Organism – e.g. anaerobe antibiogram – ASP Antibiograms – e.g. novel agents or last resort agents (colistin) • Resistance Profiles – % Susceptible for combinations of drugs – % Susceptible for groups of organisms (e.g., all GNR from blood)

Combination of Antimicrobial Agents CLSI M39-A4

Organisms resistance characteristics CLSI M39-A4

Non-Traditional Antibiograms

What About Non-Traditional Antibiograms? • Accumulate AST data outside of a single institution – Combined Regional Antibiograms – Antimicrobial Resistance Surveillance Programs (ARSP) • Creating an ARSP report – New in M39-A5 Characteristic Routine Antibiogram Non-Traditional Antibiogram Study Period Annually Defined by study # of Institutions One Multiple Presentation Table Report with I, M&M, R and D 28

When To Consider Utilizing Non- Traditional Antibiogram Data? • The use of a local cumulative antibiogram is preferred to guide initial empiric therapy • Non-Traditional antibiogram data: – Used when local AST data are not available, are limited in size or scope – Used as a benchmark to compare local data to regional and national findings 29